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71.
The failure mode of isotropic three-dimensional reticulated porous materials under compression has been investigated. A mathematical relationship between nominal main stresses and porosity has been derived for this class of materials at shearing failure under various compressive loads from the simplified structural model of an octahedron. These compressive loads cover all three loading conditions, including uniaxial compression, biaxial compression and triaxial compression. The results indicate that (1) the failure mode is relative to the material species of these porous bodies under compression, (2) the porous body of brittle material species will show the tensile fracture mode of pore struts and (3) the porous body of ductile material species will probably display the shearing fracture mode of pore struts. Through a relevant expression, the criterion of strength design can be enhanced for these porous materials under shearing failure caused by compressive loadings.  相似文献   
72.
The variable substitution and power-series techniques are used for the asymptotic analytical derivation of the governing equation of a transverse surface wave. The results reveal that the transverse wave can propagate along the surface of a functionally graded infinite half space in various modes, and that their dispersion relations are normal. For certain cases, energy is concentrated on the surface region to a depth of several wavelengths. A new theoretical foundation based on the transverse surface wave can be provided for graded-material characterization by experimental measurement. Some phenomena of seismic wave propagation may also be explained.  相似文献   
73.
ABSTRACT

The propagation of shear horizontal (SH) surface waves in piezoelectric semi-infinite bodies is investigated theoretically. The surface stress exerting on the boundary is taken into account through surface piezoelectricity theory, and the velocity ranges and existence conditions of such surface waves for both electrically open and shorted cases are derived in detail. Analysis results show that the SH surface waves occurring with surface stress are dispersive in contrast to the classical situation, and the propagation characteristics strongly depend on the relative value of surface elasticity, surface piezoelectricity and surface density.  相似文献   
74.
Previous research on the ideational process indicates that original ideas increase in frequency as an examinee works through an open-ended task. In the present investigation, ideational flexibility was evaluated to determine if ideas also become more varied and diverse. Additionally, the relationship of intelligence (IQ) with order effects of both originality and flexibility was investigated. Tests of verbal and figural divergent thinking were administered to 80 intermediate school children. The midpoint of each individual's ideational set was found, and the flexibility and originality scores of each half of the set were compared. Results indicated that flexibility and originality scores were higher in the second half than the first half of the ideational set, but there were significant differences between high- and low-originality subjects and differences between the verbal and the figural tests. The order effect was unrelated to the IQ scores of the subjects. Suggestions are made to integrate ideational flexibility into existing theories of divergent ideation.  相似文献   
75.
Some of the ethical issues involved in publishing clinical material are considered. These include the 'ownership' of such material, the responsibilities of the analyst towards patients and professional colleagues, the keeping and status of records, the nature of trust and confidentiality and its place in analysis, the question of obtaining consent for publication, the nature of consent, and its consequences for treatment. The issues of disguise, of authenticity, and of accuracy are also touched on, as is the potential role of the author's anonymity in protecting the anonymity of the patient.  相似文献   
76.
The present article purports to show that the protocol sentence debate, pursued by some leading members of the Vienna Circle in the mid-1930s, was essentially a controversy over the explanation and the real significance of the concept of truth. It is further shown that the fundamental issue underlying the discussions about the concept of truth was the relationship between form and content, as well as between logic/language and the world. R. Carnap was the philosopher who most explicitly and systematically attempted to come to grips with this problem. It is shown that the form-content distinction pervades the three most important phases of Carnap's philosophical development: the structuralist (in Der logische Aufbau der Welt), the syntactical and the semantical. His final semantical stance is essentially determined by the concept of linguistic frameworks. The article purports to demonstrate that this concept cannot be dispensed with in philosophy, but that Carnap failed to work out its ontological implications. Finally, the concept of an internal ontology is briefly delineated. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
77.
Eighteen second-grade children initially received feedback in the form of nonredeemable tokens for reducing their disruptive classroom behavior. Four types of tutoring were then introduced in a Latin Square Design: noncontingent tutoring from fifth-grade peers, contingent peer tutoring, noncontingent college tutoring, and contingent college tutoring. No significant difference was found in the level of disruptive behavior of those children tutored by fifth-grade peers or college students, but contingent tutoring was significantly effective in reducing disruptive classroom behavior.  相似文献   
78.
材料的几何属性差异对3—7岁儿童分类标准影响的研究   总被引:7,自引:3,他引:4  
以73名3—7岁儿童为被试,通过变换分类材料的几何属性(形状或大小)的差异程度,采用自由分类方法,探讨材料差异程度的变换对儿童分类标准的影响。结果表明:3—7岁儿童的分类标准均受分类材料几何属性差异变化的影响。3岁儿童的分类标准几乎完全随分类材料的变换而改变;4—5岁儿童的分类标准主要表现为随分类材料的变换而改变;6—7岁儿童的分类标准虽然有随分类材料的变换而改变的趋势,但已经表现出比较稳定的按形状分类;5—6岁是儿童分类能力发展的质的飞跃阶段。  相似文献   
79.
Bullying at workplaces is a growing problem associated with several antecedents and outcomes of psychological disorders. Extant literature shows the relationship of victimization with the owning‐up curriculum to confront bullying, but so far there is little research to cure the issue of bullying through ethics and there is no study to check the impact of ethical lessons and exercises in training materials to curb bullying at workplace. The current paper is based on a literature review of aggression and bullying, and chiefly addresses the HR practices in rescuing the people from peer victimization. Conceptually segregating supervisor‐subordinate (vertical) and peer‐peer (horizontal) bullying psychology, this paper attempts to see what possible corrective steps can be taken by senior managers, supervisors and psychologists to resolve this critical problem through interior capacities. In this paper, we have developed three propositions for conducting a future empirical investigation in connection to a cohort study. By addressing the counterproductive/deviant behavior, the present report is likely to be beneficial for psychology scientists and HR practitioners in noticing and resolving the bullying issues at the workplace for the well‐being of employees.  相似文献   
80.
This paper presents a new multi‐criteria decision model for the material handling device (MHD) selection problem in cellular manufacturing systems. Given a set of manufacturing cells based on several automatic work‐centres, the technique makes it possible to select a particular MHD for each cell in an integrated way, with different constraints being taken into consideration. The approach is based on two different multi‐attribute analyses executed with analytic hierarchy process (AHP) methodology, and a final integer linear programming including important limitations faced by the designer when making MHD investment decisions. An example using real data is provided to illustrate this methodology. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
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